An aspiring film-maker believed to have been sleeping rough on the streets to document the plight of homeless people and the impact of the bedroom tax has been found dead in a derelict hostel just three days after embarking on his project.

Lee Halpin, 26, a radio presenter who edited an arts magazine and had completed a creative writing MA, was found in the boarded-up building in Newcastle-upon-Tyne after deciding to immerse himself for a week in the world of the those living on the streets in the city.

He was making the documentary after applying for a place on an investigative journalism scheme run by Channel 4, and hoped it would demonstrate the "fearless pursuit of a story" which the scheme required of applicants.

No cause of death has yet been established and a postmortem will be held early next week. Two men, aged 26 and 30, have been arrested on suspicion of supplying a controlled drug and bailed pending further inquiries.

Friends said they believed Halpin could have suffered hypothermia in the sub-zero temperatures.

Halpin, described in numerous tributes as a "great advocate" for the north-east arts scene and who had a weekly show, The Weekend Starts Here, on Radio Tyneside, posted his video application to Channel 4 online on Sunday, three days before his body was found.

Speaking to the camera, he said he had spoken to a homeless charity about the rise in the number of people on the streets and the possible repercussions of the bedroom tax.

"I'm about to go and spend a week being homeless in the West End of Newcastle. I will sleep rough for a week, scrounge for my food, access the services that other homeless individuals use," he said.

"I will interact with as many homeless people as possible and immerse myself in that lifestyle as deeply as I can."

"I hope that you perceive this to be a fearless approach to a story. It certainly feels brave from where I'm sat right now." He added: "That's the impression I want to leave you with about my willingness to get to the heart of a story."

Poignantly, he also mentioned his family and friends had voiced trepidation about his project.

Shortly before he embarked on the film, he tweeted to his 1,500 Twitter followers asking if anyone had a sleeping bag he could borrow. He also asked if anyone had an old phone he could borrow for a week.

Daniel Lake, a friend for 10 years, told the Evening Chronicle : "I was just talking to Lee on Saturday having some banter talking about football and how excited he was about going out filming.

"Lee was a great guy, a character and was well known. His big things were creative writing and poetry. He was making a documentary about homeless people living in Newcastle's West End. No one knows how he passed away, but we think it could have been hypothermia.

"He made the ultimate sacrifice trying to raise awareness about what was happening to other people".

Having completed his creative writing MA, Halpin, who lived with his family in Heaton, Newcastle, became a founder editor of Novel, a magazine covering all aspects of north-east culture from performance and exhibitions to launch parties and talent. He was also briefly media co-ordinator at Northumbria University students' union.

David Nicholson, station director at Radio Tyneside, said news of his death had come "as a great shock".

"Lee had worked for us for just over 12 months doing an arts programme on a Friday evening. He was a very committed guy. Whatever he got his teeth into, he fully went for it."

He added Halpin had asked for a week off though did not tell him what for. "When we heard what he was doing, it didn't surprise me at all. He was the type of guy if he was going to do something he would put himself into the same situation he was reporting on.

"It's very sad news."

On Twitter, tributes were been paid by many who knew and worked with him.

Staff at Intimation Creative said: "We're very sad to hear that Lee Halpin passed away … Our thoughts go out to Lee's family and many friends."

The band Tea Pad Orchestra said: "We are very sad to hear of the death of Lee Halpin … Helped us a lot. Thanks mate and goodbye."

Dan Howarth described Lee as a "talented, courageous and thoroughly excellent bloke", adding: "Shattered by the news of the death of Lee Halpin … a massive loss."

Halpin was discovered at 9.50am on Wednesday at the boarded-up Summerhill hostel. A spokesman for Northumbria police said: "Police were informed the body of a man believed to be in his 20s had been found in a derelict building in Westgate Road. A report will be prepared for the coroner."

A Met Office spokesman confirmed the lowest recorded temperature for Newcastle early on 3 April was around -4.2C.

Channel 4's investigative journalism programme is run in conjunction with the current affairs programme Dispatches, giving aspiring television journalists the opportunity to work with a production company. Applicants submit a video and questionnaire explaining why their work is "fearless" and those who are successful receive a 12-month contract.